Slide out rooms have been used to increase the living space within a recreational vehicle. As is always the case, sealing, the slide out room can be difficult. Typically, a slide out room is constructed with two peripheral flanges that extend around the room and are larger than the opening through which the room moves. Assembly of the slide out room into the recreational vehicle would be simplified if the flanges did not extend around the room to an extent that is larger than the opening that accepts the slide out room. However, doing so would diminish the ability to seal the room using traditional construction techniques. It is desirable to have a sealing system adapted for sealing a room which has no flange extending beyond the slide out room opening.